Buy from reputable sellers. The only reason people get burned is because they think they are getting a great deal on a sign. If you dont have the knowledge to know which signs are real and which are not... then pay the premium to buy from someone that does.
Many collectors and resellers in this hobby, including myself, guarantee their items authenticity.
Wanted: Sweney Oil items - Peoria, IL
Follow Me & my Finds on Instagram: @bryce_gillespie
Collection & Items for Sale: www.OnceAlwaysPetro.com